<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <form action="/login" method="post">
    <div>
      <input type="text" name="username" value="admin" placeholder="账号">
    </div>
    <div>
      <input type="text" name="password" value='admin' placeholder="密码">
    </div>
    <div>
      <button>进入后台</button>
    </div>
  </form>
</body>

</html>